In a power tool which performs an operation such as a hammering operation or a hammer drill operation by a tool bit on a workpiece such as concrete, dust is generated during operation. Therefore, known power tools are provided with a dust suction device for sucking dust generated during operation. For example, Japanese laid-open patent publication No. 64-87304 discloses a dust suction device in which a dust suction part for sucking dust is provided on a front end of a pipe which extends in parallel to a tool bit. This dust suction device is provided to suck dust generated during operation by the dust suction part and collect the dust via the pipe and a dust transfer passage formed in the power tool body, by performing the operation with the tool bit and the dust suction part held in contact with the workpiece.
When, for example, a drilling operation is performed on a predetermined position of the workpiece, it is necessary to position the tip of a tool bit on the predetermined drilling position. Further, in order to efficiently suck dust, the tip of the tool bit has to be covered by the dust suction part. In such a construction, however, it is difficult for the user to visually check the position of the tip of the tool bit. Therefore, when the user performs an operation which requires positioning of the bit tip on a point of a workpiece to be worked, a cumbersome operation is required, for example, for checking the position of the bit tip. Specifically, while holding the power tool with one hand, the user has to move the dust suction part toward the tool body with the other hand so as to expose the bit tip to the outside in order to check the position of the bit tip. Further, in a large power tool which has to be held by user's both hands, the operation itself of exposing the bit tip to the outside is difficult to perform, Thus, the conventional power tool with the dust suction device is not easy to operate, and in this point, further improvement is desired.
Prior Art: Japanese laid-open patent publication No. 64-87304